Safety appliance for electric elevators.



G. S. GILBERT.

SAFETY APPLIANCE FOR ELECTRIC ELEVATORS.

APPLICATION FILED DEC. 28, 1908.

Patented 0t.5,1909.-

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UNITED s'rarns PATENT OFFICE.

CLARENCE S. GILBERT, OF ST. JOSEPH, MISSOURI.

SAFETY APPLIANCE FOR ELECTRIC ELEVATORS;

Specification of Letters Patent.

Application filed December 28,1908. Serial No; 469,685.

To ail whom it may concern:

Be it known't-hat I, CLARENCE S. GILBERT, of the city of St. Joseph, in the county of Buchanan and State of Missouri, have invented certain Improvements in Safety ip pliances for Electric Elevators, of which the following 1s a specification. A v

This invention has for its object to pro- .vide, in connection with a simple mechanical means, on the shaft of which wheel is inafter described and claimed and illustrated.

mounted a clutch device adapted to hold the shaft from creeping or twining when the elevator is running and top the same in some undesirable position in its travel. The clutch mechanism is operated by a solenoid or eiectro-magnet connected in shunt with the armature of the operating motor which energizes said solenoid as long as the armature rotates, thereby holding the clutch in active position and.serving as a brake for the shaft and the wheel thereon.

With these and other objects in view, the invention consists of the novel construction, combination and arrangement of parts herein the accompanying drawings, in which.

Figure 1 is a diagrammatic view of a part of an elevator with my invention applied. Fig. 2, an enlarged sectional view of the clutch in inactive position, the solenoid magnet and the electrically operating devices connected to the solenoid illustrated diagrammatically; and Fig. 3, a similar view of the clutch in operative position on a larger scale.

Like reference characters are used for the same parts in all the figures. In the drawing, the numeral 1 indicates an elevator car attached to the usual hoisting cables 2. Passing through the elevator car 1 from top to bottom is the ordinary hand rope 3, by means of which the car is started and sto ped. The hand rope 3 is stretched as usua between two wheels 4 at opposite ends of the elevator shaft,'and near the bottom of said shaft, or. at any convenient point,-

it is wound around a pulley 5 fastened on If shaft 6 which latter may or may not operate,

mechanism of the usual type for starting and stopping the elevator motor, which in this instance is an electric motor.

Fixed on the shaft 6 is a cylindrical drum 7 with a separate closed end 7 containing a 'collarS also fixed on said shaft and having a circular periphery flattened or notched on one side as at 9. The collar 8 is of less Patented Oct. 5, 1909.

diameter than the interior of the drum and V opposite sides and extended into the space 7 in the drum between the ends of the split ring 10 which bear against the said flattened sides of the aforesaid pin 13. Atfixed to the pin 13 within the drum is a finger 14 provided with a flat side, or other suitable surface capable of being drawn into contact with the periphery of the collar '8 when the pin is rocked. The outer endof the pin 13 carries a relatively long arm 15 which when moved in one direction rocks the pin and forces the finger against the collar, and when the flattened side 9 thereof is opposite the finger, said pin, becauseof its greater range of movement, presses the split ring against-the inner surface of the drum and prevents the rotation of the latter. I

Rigidly secured to the base 12 is a solenoid magnet or electro-ma net 16, the core orsaid collar, either by gravity, the resiliency of the ring, or by a supplemental spring.

The solenoid magnet is energized from the electric motor 18, which operates the elevator, in a manner now to be described,

The armature l9 and brushes 20 and 21 of the motor are connected to the mains 22 and 23 through the seriesiield winding 24 and the usual starting resistance 25. 'The shunt field windingis indicated by 26. Connected in shunt with the armature 19 of, the motor ,ing in shunt with the armature 19, it will continue to receife energy therefrom after the mam circuit through the motor-1s cut ofi until the armature ceases its rotation.

It will, therefore, be understood that as soon as a current of sufiicient strength passes through the solenoid magnet, sometimes called plunger magnet, 16, the core 17 thereof will be drawn into the magnet, and, through the connection between said core and the arm or lever 15, the pin 13 will be rocked, forcing the finger against the collar 8 and expanding the split-ring 10.

Then the motor 18 is at rest, the clutch mechanism is in the position represented in Fig. 2 with the finger 1i resting against the inner surface of the drum 7 out of contact with the flat side 9 of the collar 8, and the solenoid core 17 projecting-from the magnet.

As soon as the hand rope is drawn in either direction, the pulley 5 will be turned to the right or left for about one-half a revolution, the direction in which the pulley rotates being immaterial to the action of the device.

The shaft (3 .with the drum 7 and collar 8" also turn with the pulley, so that the curved portion of the collar is brought opposite the finger 14, see dotted lines in Fig. 2. This movement of the shaft (3 throws the electric current through the driving motor 18, energizing the same and causing it to operate the elevator, and at the same time, vitalizing the solenoid magnet through the shunt circuit from the armature. then drawn into the magnet, and, through the connection described, cause the finger 14: to bear firmly on' the circular periphery of the collar 8 to hold the wheel against creepmg or twining from any undue cause. When it is desired to stop theelevator, the hand rope is operated in the proper direction, thereby returning the collar to its normal position, as in Fig. 2; and as the solenoid is still energized by the rotating armature, the

, finger 14: will be drawn against the flattened side 9 of the collar and the split-ring forced The core 17 will be eeaiie into contact with the drum by the flattened portions on the pin 13, thus holding the clutch in rigid position until the armature ceases revolving. By this means, the pulley 5 is held stationary and the hand rope rendered immovable until the motor armature comes to a stop, thereby preventing sudden reversing of the elevator and a too rapid change in direction of travel thereof, both of which causes endanger the motor and the cables. 7

The starting resistance will preferably be any one of the Well known types which gradually cuts out resistance as the motor increases in speed and when full power has been reached all resistance will be eliminated.

Having thus described the invention, what is claimed is 1. In an electrically driven elevator, an apparatus for the purpose described, which consists in the combination of a motor, a starting rope, a pulley over which the starting rope is wound, a clutch brake to affect the rotation of the pulley, a solenoid, to control the brake, the solenoi being energized through a shunt circuit fr 111 'the armature of the motor, substantially as specified.

2. An electrical attachment to control the movement of the starting rope of an elevator, which consists in the combination of a motor, a pulley over which the starting .rope is wound, a clutch brake adapted to hold the starting rope through the medium of the pulley and clutch brake, a solenoid adapted. to operate the clutch brake, the said solenoid being energized by a shunt circuit from the armature of the motor, substantially as specified.

3. An attachment for an electrically operated elevator, to prevent accidental movement of the starting rope, which consists of a pulley oscillated by the said starting rope, a clutch brake for the pulley and a solenoid for operating the clutch brake, combined with an electric motor which operates the elevator, the said solenoid being energized by a shunt circuit from the armature of the said motor, substantially as specified.

' CLARENCE S. GILBERT.

Witnesses:

J. C. Annnrolrr, M. R. CRAWFORD. 

